PR tree-optimization/50693

	* tree-cfg.c (gimple_can_merge_blocks_p): Allow merging with
	non-forced user labels.
	(gimple_merge_blocks): Turn non-forced user labels into
	debug bind stmt with the label as first operand and reset value.
	(gimple_duplicate_bb): Don't duplicate label debug stmts.
	* dwarf2out.c (gen_label_die): Handle NOTE_INSN_DELETED_DEBUG_LABEL.
	* final.c (final_scan_insn): Likewise.
	(rest_of_clean_state): Don't dump NOTE_INSN_DELETED_DEBUG_LABEL.
	* var-tracking.c (debug_label_num): New variable.
	(delete_debug_insns): Don't delete DEBUG_INSNs for LABEL_DECLs,
	instead turn them into NOTE_INSN_DELETED_DEBUG_LABEL notes.
	* cfglayout.c (skip_insns_after_block, duplicate_insn_chain): Handle
	NOTE_INSN_DELETED_DEBUG_LABEL.
	(duplicate_insn_chain): Don't duplicate LABEL_DECL DEBUG_INSNs.
	* insn-notes.def (DELETED_DEBUG_LABEL): New note kind.
	* print-rtl.c (print_rtx): Handle NOTE_INSN_DELETED_DEBUG_LABEL.
	* gengtype.c (adjust_field_rtx_def): Likewise.
	* config/i386/i386.c (ix86_output_function_epilogue): For MachO
	clear CODE_LABEL_NUMBER of NOTE_INSN_DELETED_DEBUG_LABEL
	if their are at the end of function and nop hasn't been emitted.
	* config/rs6000/rs6000.c (rs6000_output_function_epilogue): Likewise.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@181014 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 22 insertions, 1 deletions

diff --git a/gcc/var-tracking.c b/gcc/var-tracking.c
index 11d4efdcdc2..95bc02b183c 100644
--- a/gcc/var-tracking.c
+++ b/gcc/var-tracking.c
@@ -9517,6 +9517,12 @@ vt_initialize (void)
   return true;
 }
 
+/* This is *not* reset after each function.  It gives each
+   NOTE_INSN_DELETED_DEBUG_LABEL in the entire compilation
+   a unique label number.  */
+
+static int debug_label_num = 1;
+
 /* Get rid of all debug insns from the insn stream.  */
 
 static void
@@ -9532,7 +9538,22 @@ delete_debug_insns (void)
     {
       FOR_BB_INSNS_SAFE (bb, insn, next)
 	if (DEBUG_INSN_P (insn))
-	  delete_insn (insn);
+	  {
+	    tree decl = INSN_VAR_LOCATION_DECL (insn);
+	    if (TREE_CODE (decl) == LABEL_DECL
+		&& DECL_NAME (decl)
+		&& !DECL_RTL_SET_P (decl))
+	      {
+		PUT_CODE (insn, NOTE);
+		NOTE_KIND (insn) = NOTE_INSN_DELETED_DEBUG_LABEL;
+		NOTE_DELETED_LABEL_NAME (insn)
+		  = IDENTIFIER_POINTER (DECL_NAME (decl));
+		SET_DECL_RTL (decl, insn);
+		CODE_LABEL_NUMBER (insn) = debug_label_num++;
+	      }
+	    else
+	      delete_insn (insn);
+	  }
     }
 }